KR0145911B1 - Apparatus for correcting luminous intensity for projector - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screen luminance difference correction value of a projection type image display system, wherein an AMA panel in which a plurality of pixel driving elements for driving a plurality of pixels for reproducing incident light corresponding to an image signal in an optical modulation manner is arranged in a matrix array form. (16) and row / column driving circuit sections 76, 78 for matching the image signals with the image data for the AMA 16 and for performing row / column driving of a plurality of speech drive elements provided in the AMA 16; In the projection-type image display system having a light emitting device, a brightness correction data for a reflection angle error of the data conversion unit 60 and the AMA pattern 16 converting the image signal optically modulated by the AMA panel 16 into digital data. The data conversion and the brightness correction based on the synchronization compensation signal separated by the brightness correction data storage unit 66 and the brightness correction data storage unit 68 for loading and outputting the brightness correction data stored therein. data An address / control signal generation unit 64 for generating an address and a control signal for controlling the loading / output, data of the digitally converted image signal, and luminance correction data applied through the luminance correction data storage unit 68; And a luminance correction circuit section 70 for correcting each pixel in correspondence with a pixel matching method, wherein the luminance correction data is irradiated with test light in a state in which no image signal is applied to the AMA panel 16. It is set by measuring the center luminance and the ambient luminance of the screen and calculating the threshold value.

Description

Screen Luminance Correction System of Projection Image Display System

1 is a schematic diagram for explaining a configuration example of a projection image display system to which the present invention is applied.

2 is a view for explaining a typical structural example of the AMA member constituting the AMA panel as the optical modulation member shown in FIG.

3 is a block diagram showing a screen luminance difference correction apparatus of a projection type image display system according to the present invention.

4 (a) and 4 (b) are diagrams illustrating the differences in light intensity at the center and periphery of a screen applied to the screen light intensity correction apparatus of the projection type image display system shown in FIG. It is a figure explaining the degree of correlation with correction data.

* Explanation of symbols for main parts of the drawings

10: light source lamp 12: source stop member

14: field lens 16: reflective optical modulation member (AMA panel)

18: Projection stop member 20: Projection lens

30: active matrix substrate 40: actuator

60: data conversion section 62: synchronous separation section

64: address / control signal generator 66: luminance correction data storage (ROM)

68: light intensity correction data storage 70: light intensity correction circuit

72: field memory 74: data inverse converter

76: row drive circuit portion 78: column drive circuit portion

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a screen luminance difference correcting apparatus of a projection image display system, and more particularly, based on reflected light formed by the AMA panel in a projection image display system having an AMA panel for reproducing an image by a light modulation method. The present invention relates to a screen luminance difference correcting apparatus of a projection type image display system configured to correct a luminance difference at a center and a periphery of a screen to obtain a uniform brightness of the screen as a whole.

In general, a CRT apparatus, a direct-view display apparatus employed as an image display apparatus in televisions or the like, forms an R, G, B fluorescent point for one pixel on the fluorescent panel, and forms a black stripe. Correspondingly, when the light beam irradiated from the R · G · B electron gun is incident on any one of the R · G · B fluorescent points, the corresponding fluorescent point emits light to display the color image.

According to such a CRT apparatus, when the electron beam flows between the electron gun and the fluorescent panel, such a direct view image is usually generated because the distortion of the screen is generated by the distance difference between the center part and the periphery of the screen (especially the corner part). In the display device, so-called 'S-calibration' is performed on the screen in hardware to ensure the uniform brightness of the image as a whole.

On the other hand, according to the recently proposed projection type image display system, the light emitted from the light source is shaped into a predetermined pattern, which is reflected at an angle proportional to the image signal voltage, and then is projected onto the screen through the projection lens.

1 is a diagram showing a configuration example of such a projection type image display system, wherein reference numeral 10 denotes a light source lamp for emitting light for image display, and 12 denotes a quantity of light emitted from the light source lamp 10 in a constant shape. A source stop member having an area 12a for the purpose of operation is shown, and 14 denotes a field lens for condensing light passing through the source stop member 12.

In addition, 16 represents a plurality of reflecting mirror members, such as an AMA (Actuated Mirror Array) member, which adjusts the reflection angle with respect to the incident light in the form of light collected by the field range 14 based on the image signal voltage. 18 shows a reflection type optical modulation member (AMA panel), and transmits the light reflected by the reflection type optical modulation member 16 to the projection lens 20 through the projection area 18a in the form of gradation conversion. Represents a projection stop member for projecting on a screen.

Here, the AMA pattern 16 as the light reflection member is formed of the AMA member having the structure shown in FIG. 2, that is, a plurality of pixels composed of, for example, MOS transistors to drive the entire pixel constituting one screen. On the active matrix substrate 30 in which drive elements (not shown) are arranged in a matrix array, signal electrode pads 32 corresponding to the pixel driving elements are formed.

In addition, an actuator 40 is formed on the active matrix substrate 30 corresponding to the signal electrode pad 32. The actuator 40 places the actuator 40 on the active matrix substrate 30. A support member 42 for supporting and a membrane 44 having a predetermined length stacked on the support member 42, a plug laminated on the membrane 44 and penetrating the support member 42 and the membrane 44. A lower electrode 48 electrically connected to the signal electrode pad 32 via a 46, a deformable portion 50 formed by laminating piezoelectric materials on the lower electrode 48, and the deformable portion 50. The upper electrode 52 which acts as a common electrode formed by laminating aluminum on the upper surface, and also acts as a reflective layer reflecting incident light when the actuator 40 is inclinedly driven by the image signal voltage applied from the signal electrode pad 32. It is configured with).

Accordingly, the actuator 40 is electrically connected to the signal electrode pad 32 to perform inclined driving in proportion to the image signal voltage applied to the signal electrode pad 32 in the corresponding pixel driver. Light modulation is performed by adjusting the reflection angle.

Therefore, in the projection type image display system shown in FIG. 1, light emitted from the light source 10 and shaped into a constant light form at the source stop member 12 is incident on the AMA panel 16 through the field lens 14. Accordingly, as described above, when the image signal voltage is applied to the pixel array element of the matrix array type formed on the active matrix substrate 30 constituting the AMA panel 16, the actuator formed on the active matrix substrate 30. 40 is tilted in proportion to the applied image signal voltage.

By the inclination of the actuator 40, the angle of incidence of the incident light, which is turned forward from one surface of the light modulation member 16, is adjusted, and the adjusted light is transmitted through the field lens 14 to the projection stop member 18. And the projection lens 20 are sequentially provided, and thus image reproduction is possible by projecting an image controlled by the projection lens 20 onto the screen 22.

Therefore, in the projection type image display system configured as described above, the light generated by the light source lamp 10 passes through the source stop member 12 and is condensed by the field lens 14 to form the AMA panel 16 which is a reflective optical modulation member. ), The light reflected from the AMA panel 16 is incident on the projection stop member 18 via the field lens 14, and the light incident on the projection stop member 18 is the AMA panel. In 16, it is transmitted to the projection lens 20 according to the degree of inclination of each reflective mirror member (i.e., AMA member-see FIG. 2).

By the way, according to such a projection type image display system, the light intensity difference between the center portion and the peripheral portion in the light intensity incident on the AMA panel 16 by the light intensity difference irradiated from the center portion and the peripheral portion of the light source 10 (approximately) 5: 1 to 7: 1) is generated, and therefore, even in the screen of the image projected on the screen by the projection lens 20, the light intensity difference between the central portion and the peripheral portion becomes remarkable, so that the brightness of the entire screen is not uniform. This results in deterioration of image quality.

Accordingly, the present invention has been made in view of the above-described circumstances, and the correction data is generated in advance for the screen luminous differences on the AMA panel resulting from the luminous differences between the central and peripheral portions of the light irradiated from the light source, and the correction data at the time of driving the pixels. It is an object of the present invention to provide a screen luminance difference correction apparatus of a projection type image display system in which the luminance difference is eliminated by using the same.

In order to achieve the above object, according to a preferred embodiment of the present invention, an AMA panel in which a plurality of pixel driving elements for driving a plurality of pixels for reproducing the incident light corresponding to an image signal in a light modulation manner is arranged in a matrix array form; A projection type image display system having row / column driving means for matching the image signal with image data for the AMA panel and row / column driving a plurality of pixel driver elements provided in the AMA panel. Data conversion means for converting the optical signal modulated by the optical signal into digital data, brightness correction data storage means for storing the brightness correction data for the reflection angle error of the AMA panel, and light correction data storage means for loading and outputting the brightness correction data. Controlling the data conversion and loading / output of the brightness correction data based on the synchronization signal separated by the synchronization separation means. Address / control signal generation means for generating a control signal, data of a digitally-converted video signal, and luminance correction data applied through the image data storage means in a pixel matching method for correction of each pixel. A screen luminance difference correction apparatus of a projection type image display system including a brightness correction means to be provided is provided.

Preferably, the brightness correction data is set by irradiating test light (white light) in the state that no image signal is applied to the AMA panel, measuring the center brightness and the ambient light, and calculating the threshold value.

According to the present invention configured as described above, the AMA panel is irradiated with white light as a test light to obtain the light intensity difference between the central part and the periphery reflected by the AMA panel, and then the threshold value for the light difference is created as compensation data to display the actual screen. In this case, by providing the luminance correction data additionally, the luminance difference between the central portion and the peripheral portion of the screen can be eliminated.

Hereinafter, with reference to the accompanying drawings, the present invention will be described in detail.

3 is a block diagram of a screen luminance difference correcting apparatus of a projection image display system according to a preferred embodiment of the present invention. Reference numeral 60 denotes a light by an AMA panel indicated by reference numeral 18 constituting the projection image display system. When an image signal Vin for modulating and reproducing is R / G / B coded and applied, it represents a data conversion section comprising an analog-digital converter for converting the R / G / B color signal into digital data. A synchronization separator for separating the horizontal synchronization signal Hsync and the vertical synchronization signal Vsync (and color subcarrier fsc (about 3.58 MHz)) from the image signal Vin.

In addition, 64 is a combination of the vertical synchronization signal (Vsync), the horizontal synchronization signal (Hsync) and the clock signal (CLK; 4fsc, fsc is the color sub-carrier frequency) separated by the synchronization separation unit 62, the screen display and the brightness difference An address / control signal generator for generating an address signal and a control signal applied to access of data for correction, and the address / control signal generator 64 corresponds to a vertical sync signal Vsync and a horizontal sync signal Hsync. The clock signal CLK is divided in synchronization with each other to generate an address and a control signal for driving a pixel. For example, assuming a screen of 640 x 480, the total number of pixels on the screen is 307,200. The address needed to drive is 2 ^{0-2 18} .

Therefore, the address / control signal generation unit 64 combines the horizontal synchronous signal Hsync and the vertical synchronous signal Vsync separated by the synchronous signal separating means, as is well known, to synchronize the clock signal with the combined result. Is divided to generate an address for the pixel composition.

66 is a luminance correction data constituted by, for example, a semiconductor memory (ROM) in which correction values for the luminance difference between the center and the periphery of the screen are stored as the luminance correction data during the light reflection by the pixel driving elements constituting the AMA panel 16. As shown in the storage unit, the luminance correction data stored in the luminance correction data storage unit 66 irradiates white light as test light to the AMA panel 16, and then calculates the luminance difference between the central portion and the luminance correction peripheral portion. ROM table is created. That is, when the white light is irradiated to the AMA panel 16, the luminance of the center and the periphery of the AMA panel 16 generally has a Gaussian distribution as shown in FIG. As shown in FIG. 4 (b), the luminance correction data is generated by the inverse Gaussian distribution with respect to the luminance difference of the Gaussian distribution assumed in the present invention.

Further, reference numeral 68 denotes the luminance correction if the pixel-level correction data for the luminance correction data corresponding to the address generated by the address / control signal generation unit 64 is read from the luminance correction data storage unit 66. A luminance correction data storage portion configured, for example, of RAM, in which data is temporarily stored in response to a control signal provided from the address / control signal generation portion 64 and then output again.

70 denotes a pixel matching method for the image data digitally converted by the data conversion unit 60 constituted by the analog-digital converter and the luminance correction data provided through the brightness correction data storage unit 68 corresponding to the image data. A luminance correction circuit for outputting pixel driving data corrected by applying the luminance correction data to each pixel in correspondence, and 72 denotes the address / control signal generation unit for image data corrected by the luminance correction circuit unit 70; A field memory which receives and stores based on the control signal generated at 64 and sequentially outputs it is shown, and 74 denotes the address / control signal generation unit for outputting luminance correction data sequentially output from the field memory 72. A data inverse converting section constituted of a digital-analog converter for digital-analog conversion under the control of 64).

76 denotes a row drive circuit unit for driving the pixel unit actuator provided in the AMA panel 16 based on the image data analog-converted by the data inverse conversion unit 74 with respect to the AMA panel 16. Based on the address provided from the address / control signal generation unit 64 to the AMA panel 16, the pixel driving element is specified in pixel matching with the row driving circuit unit 76 so as to correspond to the corresponding AMA member (see FIG. 2). ) Shows a column driving circuit section for tilt driving.

Therefore, in the screen luminance difference correction apparatus of such a projection image display system, the data conversion unit is controlled by a clock signal CLK (4fsc) obtained by synchronizing separation of the image signal Vin to be reproduced by the synchronization separation unit 62. At 60, the digital data is converted to digital data, and applied to the image correction circuit unit 70. In this state, the address / control signal generation unit 64 reads the luminance correction data of the entire screen as described above. ) And a control signal (record (RD), read (WE), etc.) to load the luminance correction data from the luminance correction data storage unit 66 to the luminance correction data storage unit 68 and then the luminance correction circuit unit 70 Will be output as

That is, the luminance correction data storage unit 66 stores luminance correction data in pixel units at positions corresponding to addresses Ad sequentially provided from the address / control signal generation unit 64. The luminance correction data storage unit 68 temporarily stores the luminance correction data based on the control signal provided from the address / control signal generation unit 64, and then sequentially adjusts the luminance correction circuit unit (I). 70).

Therefore, the brightness correction loop 70 matches and corrects the brightness correction data (see FIG. 4 (b)) provided by the brightness correction data storage unit 68 with respect to the digitally converted video signal. The pixel drive data is applied to the data inverse converter 74 via the field memory 72 controlled by the clock signal CLK, and the data inverse converter 74 uses the clock signal CLK. The control is performed to analog convert the luminance-compensated pixel drive data and then provide it to the row drive circuitry 76.

In this state, the column driver circuit portion 78 designates the pixel driver elements in the column direction based on the address for pixel driving applied from the address / control signal generator 64, and the designated pixel driver elements In response to the pixel driving data applied from the row driving circuit section 76, the actuator 40 of the AMA member is tilted to reflect the light incident on the AMA panel 16, and then projected onto the screen through the projection lens. It will work.

As described above, according to the screen luminance difference correcting apparatus of the projection type image display system according to the present invention, the white light is irradiated to the AMA panel to obtain the photoluminescence difference between the central part and the peripheral part of the reflected light reflected from the AMA panel, and then the optical difference. By generating the threshold for the image as compensation data and applying the luminance correction data in the case of image display, the luminance difference between the center and the periphery of the screen can be eliminated to obtain a remodeled image quality.

Claims (3)

AMA panel 16 in which a plurality of pixel driving elements for reproducing incident light corresponding to an image signal in a light-modulated manner is arranged in a matrix array form, and the image signal and the AMA panel 16 A projection type image display system comprising row / column driving means (76,78) for matching image data and row / column driving a plurality of pixel driving elements provided in the AMA panel (16), wherein the AMA panel (16) Data conversion means 60 for converting the image signal optically modulated by the digital signal into digital data, and the brightness correction data storing means 66 storing the brightness correction data for the reflection angle error of the AMA panel 16 and the brightness correction thereof. Address and control signals for controlling the data conversion and loading / output of the brightness correction data on the basis of the synchronization signal separated by the brightness correction data storage means 68 and the sync separation means 62 for loading and outputting data. Address / control signal generating means (64) for generating a signal, and data of the digitally converted video signal and luminance correction data applied through the image data storing means (68) in a pixel matching method for correction for each pixel. And a brightness correction means (70) to perform the screen brightness difference correction apparatus of the projection type image display system. The method of claim 1, wherein the brightness correction data is set by irradiating test light in a state where no image signal is applied to the AMA panel 16, by measuring a center brightness and an ambient light intensity of a screen and calculating a threshold thereof. Screen luminance difference correction device of a projection type image display system. 3. The apparatus of claim 2, wherein the test light irradiated to the AMA panel (16) when the brightness correction data is set is white light.